Amorphous polyolefins are well known and are very useful in adhesives, roofing compositions, cable filling, cable flooding, and caulk and sealants. Amorphous polyolefins are produced and then transferred or shipped in many different forms for incorporation into final compositions. Amorphous polyolefins are generally tacky at room temperature and have a low degree of crystallinity and therefore are not easily formed into powders or pellets for shipment. Amorphous polyolefins are generally transferred in the molten state in large containers, as small slats coated with a non-tacky substance packaged in corrugated containers, or small and large blocks packaged in a release coated paper container.
The most preferred form to transfer amorphous polyolefins is in the bulk molten form. The bulk molten form is preferred due to its low processing cost. However, the bulk molten form is shipped in large containers such as tank cars and many end users do not have the capability to unload or store these large quantities of molten amorphous polyolefins. Therefore, many end users prefer amorphous polyolefin packaged in an economical and easy to use solid form.
Compounders or end users of the amorphous polyolefin prefer forms of the solid amorphous polyolefin that are easy to handle. Amorphous polyolefin pellets would be most desirable, however, their production is very difficult and they are not commercially available. Thus, of the available forms, amorphous polyolefin slats are generally the form most preferred and easiest to handle. However, slats are expensive to manufacture and thus increase the raw material cost to the end user.
In light of the above, the form most economical to use is the amorphous polyolefin in solid blocks. However, the use of the solid block form of amorphous polyolefin is very labor intensive, requiring the end user to remove the coated paper prior to blending. The paper is often adhered to the APO and difficult to remove and also generates solid waste. The larger solid form i.e. 50 pound package is generally preferred over the 20 pound package due to the reduced time spent to remove the package from around the block per any given amount of amorphous polyolefin. A solid form that is cheap yet does not require the labor to unwrap would be very desirable for the end users.
It is known to enclose slabs of material in a film that is later incorporated into the composition without being unwrapped such as disclosed in FR 2,608,560 and DE 1,511,577. However, these process involve elaborate filling and cooling steps.
In light of the above, it would be very desirable to be able to cheaply produce amorphous polyolefins in a solid form that could be easily incorporated or blended with other materials to reduce the cost of the final composition.